Congenital and acquired abnormalities observed in live-born and stillborn neonates.

This report records the congenital and acquired abnormalities observed during the first 4 days of life in 21,142 live-born infants. Gross abnormalities observed in 300 stillborns also are recorded. The abnormalities are those thought to be of clinical or possibly clinical significance. Also included are other conditions ordinarily not considered to be a congenital abnormality, such as convulsions. Definitions are given when indicated. The incidence rates per 1,000 births for specific malformation noted in the first 4 days of life are provided for all births, for live births, for live births under 2,500 g, and for stillbirths. The need for accurate studies of specific forms of congenital malformations is reiterated. The rate for all malformations combined is not given since it is difficult to interpret or use for comparisons because of variations in the definition of malformation and in completeness of ascertainment in different studies.